Description
A serious threat to both indoor and outdoor dogs, heartworm is a disease caused by a worm called Dirofilaria immitis. The parasite is transmitted to dogs by mosquitoes carrying immature heartworms that they get from biting animals infected by the parasite. The immature worms circulate in the bloodstream and then migrate to the right side of the heart and pulmonary arteries where they mature and can live as adults for up to five years. Adult heartworms can grow to be as long as 14 inches and up to 100 or more worms can be living at one time. Heartworms cause serious and sometimes fatal diseases, so prevention and treatment of infected dogs is critical.